docs(hacktoberfest): expand contributor onboarding beyond label stub

[ulises-jeremias]

Context

docs/HACKTOBERFEST.md is only a short stub. New contributors need a clearer map of repos and labels.

Steps

1. Expand docs/HACKTOBERFEST.md to list repos newcomers can touch (create-python-app, cpa-templates, website, taps).
2. Explain good first issue, help wanted, and seasonal Hacktoberfest labeling.
3. Link CONTRIBUTING files and Discord.
4. Note that assigned epics (e.g. AI/ML catalog) should not be duplicated casually.

Acceptance criteria

• Doc is roughly 40–80 lines with actionable links
• Repo table or bullet list with example task types
• Discord + CONTRIBUTING links present
• Explicit guidance about assigned epics

Files

• docs/HACKTOBERFEST.md
• Optional cross-link from root README.md

How to verify

A newcomer can pick a repo and label to search after reading the doc alone.

[PUSHPAK-JAISWAL]

@ulises-jeremias , I’d like to take on this issue. It’s a documentation-focused contribution that improves onboarding for new contributors by documenting the offline fixture workflow for CLI testing and expanding the Hacktoberfest guidance. I can complete it in a small, self-contained PR without broad code changes.

i would also liked to assigned for #248 and #247